Hearing Assessment

Part of the vestibulocochlear system assessment involves evaluating the client’s hearing. This assessment provides information on the sensorineural and conductive processes and potential problems.

Sound waves are conducted through the ear canal and the tympanic membrane. The vibrations set the ossicles of the middle ear in motion and then move fluid within the cochlea of the inner ear, in turn stimulating thousands of nerve endings. The vibrations are then transformed into electrical impulses that travel to the brain along the cochlear portion of CN VIII (vestibulocochlear nerves) (Stangor & Walinga, 2014).

Testing can begin with the client sitting on the exam table. Before testing the vestibulocochlear nerves, ask the client about any history of impaired hearing and use of hearing devices. If the client wears a hearing aid, they should keep it on.

The following rudimentary hearing tests can be done by nurses and require no specialized equipment.

1. General ability: Begin by noting the client’s general ability to hear you throughout your ongoing assessment process. For example, have you noticed any difficulties in hearing as manifested by leaning forward, appearing to lipread, or frequently asking you to repeat yourself?
2. Finger/thumb rub test: This test helps evaluate the cochlear nerve. Ask the client to look straight forward and place their index finger on the tragus of the right ear and push the tragus in and move in a circular motion until you ask the client to stop. It may be simplest to demonstrate this for them. Ask them to close their eyes so you are specifically testing hearing and not their ability to see your hand moving. Then, place your hand in front of the opposite ear (left ear) and rub your fingers and thumbs together and ask them if they can hear it. Repeat on the other side. See Video 3.

• • Normally, the client should be able to hear the sounds in both ears with a similar intensity.
    
  • Abnormal findings are when the client cannot hear the sounds or if the sounds differ in intensity

Video 3: Finger/thumb rub test. [0.40 seconds].

3. Whisper voice test: This test also helps evaluate the cochlear nerve. Tell the client that you are going to whisper a combination of three numbers and/or letters and you want them to repeat what you say. Ask them to look straight forward and place their index finger on the tragus of the right ear and push the tragus in and move their finger over the tragus in a circular motion until you ask them to stop. Stand on their left side (slightly behind them and about an arm’s length away) to test the left ear. Take a breath in, and as you breathe out, whisper a mixture of three numbers/letters (e.g., 8, E, 4). The client should be able to repeat what you say. If they don’t, whisper another set of three numbers/letters (e.g., 2, K, 10). Repeat on the opposite ear with a different set of numbers/letters. See Video 4.

• • Normally, the client can repeat what you say into both ears. If you need to repeat the set of numbers/letters on one ear (for a total of six), a normal finding is if the client is able to repeat at least half of the numbers/letters.
    
  • Abnormal findings are when the client is unable to repeat the set of numbers/letters for one or both ears, or unable to repeat at least half of them if the test is repeated twice.

Video 4: Whisper voice test. [0.50 seconds].

4. Note the findings:
   

• • Normal findings might be documented as: “Cochlear nerve test: With whispered voice test, client able to hear and repeat numbers and letters in both ears, able to hear examiner rubbing fingers together beside both ears.”
    
  • Abnormal findings might be documented as: “Client unable to hear and repeat numbers and letters whispered in left ear.”

Activity: Check Your Understanding

References

Stangor, C., & Walinga, J. (2014). Introduction to psychology – 1st Canadian edition.
https://opentextbc.ca/introductiontopsychology/